This invention relates generally to an explosion suppression system and, more particularly, to an explosion suppression system in which a dry powder suppressant is discharged in response to detection of an explosive condition.
High rate discharge (HRD) extinguishing systems are extensively used to suppress potentially destructive dust and vapor explosions occurring in inherently hazardous processes and applications. A typical HRD suppression system is disclosed in U.S. Pat. No. 2,766,832. Most commonly employed in HRD systems were halogenated liquid suppressants which are currently being replaced by environmentally friendly dry powder suppressants such as sodium bicarbonate and mono-ammonium phosphate. It has been found, however, that when dry powder suppressants are used in conventional HRD containers, the reliability of suppressant discharge is reduced. The reduced reliability results from an increased difficulty in rupturing with explosive charges the closure members typically used on the HRD containers. Since the dry powder suppressant is pressurized with a compressible gas such as nitrogen, the gas tends to absorb the shock wave created by firing of the explosive initiator to thereby attenuate the strength of the shock wave transmitted to the frangible closure member.
The object of this invention, therefore, is to provide an improved HRD explosion suppression system employing a dry powder suppressant.